Please use this identifier to cite or link to this item:
- Effect of polyol excess on the electrical property of vegetable-polyurethane film
- Universidade Estadual Paulista (UNESP)
- Universidade de São Paulo (USP)
- Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
- Freestanding castor oil-based polyurethane (PU) film was obtained using spin-coating method. The effect of polyol content was analysed by means of thermally stimulated depolarisation current and AC dielectric measurements techniques. Two relaxation peaks were observed in the temperature range of -40 to 60 degrees C for PU with different polyol contents. The presence of polyol excess provides a shift to lower temperature of the a relaxation and the decrease in the activation energy of the transition in this region might be attributed to the plasticising effect of the polyol. The peak at higher temperature is due to the Maxwell-Wagner-Sillars relaxation, which also shifts in the low temperature direction as the polyol content is increased.
- Journal of Materials Science. New York: Springer, v. 43, n. 16, p. 5436-5440, 2008.
- Acesso restrito
There are no files associated with this item.
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.